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Extreme Programming

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12 Practices

• The Planning Game• Small Releases• System Metaphor• Simple Design• Continuous Testing• Refactoring

• Pair Programming• Collective Code

Ownership• Continuous Integration• 40-Hour Work Week• On-Site Customer• Coding Standards

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An activity for your groups

• Which 6 of these 12 would be most easily adopted by your own group, and why?

• A follow-up for next week – Asking people in other groups about these practices.– As part of the project / presentation

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Day to day life on an XP team

• Hint: starts with a daily “standup” meeting much like Scrum’s scrum

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How does XP remove the need for extensive up-front requirements analysis?

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Or,

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How does XP remove the need for extensive design?

• What about API conflicts?• What about the code getting bad?• What about making bad design decisions and

finding out about it later?

“simplest thing that could possibly work”

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How does XP remove the need for extensive testing?

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What are the limits?

• *The Planning Game• Small Releases• System Metaphor• *Simple Design• *Continuous Testing• Refactoring

• Pair Programming• Collective Code

Ownership• *Continuous Integration• 40-Hour Work Week• *On-Site Customer• Coding Standards

* Are all of these inherently harder?

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The difficulties of “the customer”

• Custom development situation…– (one customer for this

particular version)

• Product development situation…– (use customer multiplier

– Myhrvold’s law)

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Question for your groups – What about different stakeholders?

• What if you have:– Client – pays for it– Users – do day-to-day use– Service people – fix it– Their managers– Customers of the buying organization / general

public• How do you ensure they are all represented?

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Adding more programmers to an XP project

• How many before relationships have to be more formal?

• Can they be remote?

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The even more extreme XP

• “Mob programming”

• See the silent movie on YouTube:https://www.youtube.com/watch?v=p_pvslS4gEI

• Basics – see http://mobprogramming.org

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XP - How much role fuzziness?

• Where does XP stand on the grounds of:– Defining clear responsibilities and holding people

accountable for those?– Having a clear message from leadership to

followers?– Self-organizing teams?

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Management theory tangent – Self-organizing teams

• What’s it mean? We asked last week…– In physics, “self-organization” means organization arises out of local

interactions.– An initially disordered system.– This is Empiricism in action!

• In management, “organization” means who-does-what.• All of agile claims to have this.

– Including Scrum.• See discussion athttp

://www.mountaingoatsoftware.com/presentations/leading-a-self-organizing-team

• Leadership is distributed and changing.• Control is subtle – “Light touch and adaptive.”

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In physics…

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How this relates to XP

• Typically teams need to transition to being “self-organizing.”

• XP teams especially need a Mentor at first.• Doing it on a daily basis – a big change.• Mentor does these things:– Removing misconceptions– Planning the transition to XP– Clearing up insecurities, gaining confidence– Taking away “finger pointing,” negativity– Helping create first cycles of successes

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Other “roles” with Agile

• Like Mentor, these surround the self-organizing team.• The customer role isn’t exactly as fluid as the team roles.

– Likely need a Coordinator to manage customer relationship.– Helps customer manage list of requirements.

• May also need a Translator– The old role of Business Analyst

• A Champion gains upper-management support for use of agile processes.

• A Promoter does similar work with customers.• A Terminator removes people from the team.

– This is a controversial role!

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Your questions from the reading quiz

• My pick• Your choice